Geochemistry,mineralogy and petrogenesis of the northeast Niğde volcanics,central Anatolia,Turkey

The volcanics exposed in the northeast Niğde area are characterized by pumiceous pyroclastic rocks present as ash flows and fall deposits and by compositions ranging from dacite to rhyolite. Xenoliths found in the volcanics are basaltic andesite, andesite and dacite in composition. These rocks exhibit linear chemical variations between end‐member compositions and a continuity of trace element behaviour exists through the basaltic andesite–andesite–dacite–rhyolite compositional range. This is consistent with the fractionation of ferromagnesian minerals and plagioclase from a basaltic andesite or andesite parent. These rocks are peraluminous and show typical high‐K calc‐alkaline differentiation trends with total iron content decreasing progressively with increasing silica content. Bulk rock and mineral compositional trends and petrographic data suggest that crustal material was added to the magmas by subducted oceanic crust and is a likely contaminant of the source zone of the Niğde magmas. The chemical variations in these volcanics indicate that crystal liquid fractionation has been a dominant process in controlling the chemistry of the northeast Niğde volcanics. It is also clear, from the petrographic and chemical features, that magma mixing with disequilibrium played a significant role in the evolution of the Niğde volcanic rocks. This is shown by normal and reverse zoning in plagioclase and resorption of most of the observed minerals. The xenoliths found in the Niğde volcanics represent the deeper part of the magma reservoir which equilibrated at the higher pressures. Copyright © 2002 John Wiley & Sons, Ltd.     

Identification of important marine areas using ecologically or biologically significant areas (EBSAs) criteria in the East to Southeast Asia region and comparison with existing registered areas for the purpose of conservation

The biodiversity of East to Southeast (E–SE) Asian waters is rapidly declining because of anthropogenic effects ranging from local environmental pressures to global warming. To improve marine biodiversity, the Aichi Biodiversity Targets were adopted in 2010. The recommendation of the Subsidiary Body on Scientific, Technical and Technological Advice (SBSTTA), encourages application of the ecologically or biologically significant area (EBSA) process to identify areas for conservation. However, there are few examples of the use of EBSA criteria to evaluate entire oceans. In this article, seven criteria are numerically evaluated to identify important marine areas (EBSA candidates) in the E–SE Asia region. The discussion includes 1) the possibility of EBSA criteria quantification throughout the E–SE Asia oceans and the suitability of the indices selected; 2) optimal integration methods for criteria, and the relationships between the criteria and data robustness and completeness; and; 3) a comparison of the EBSA candidates identified and existing registered areas for the purpose of conservation, such as marine protected areas (MPAs). Most of the EBSA criteria could be quantitatively evaluated throughout the Asia-Pacific region. However, three criteria in particular showed a substantial lack of data. Our methodological comparison showed that complementarity analysis performed better than summation because it considered criteria that were evaluated only in limited areas. Most of the difference between present-day registered areas and our results for EBSAs resulted from a lack of data and differences in philosophy for the selection of indices.     

Experimental study of impact of a certain polluted river on groundwater along river bank in Southeast China

Based on the large scale land and resources survey project--groundwater contamination survey in southeast China, a certain polluted river and its typical sites along its bank were selected as research objectives. Such river is a comprehensive sewage channel for certain provincial capital city, with complicated types of pollutants. Based on the analysis on water level of horizonal and vertical hydrogeologic profile and water quality monitoring data, the impact and range of the polluted river on local groundwater were evaluated. Data show that the polluted river supplies water to underground aquifers throughout the year, which has great impact on groundwater horizontally, but different ions have different responses. Major influential indexes such as inorganic component 3-nitrogen, sulphate, chloride etc. present an obvious relevance, while iron, manganese, fluoride, arsenic and heavy metal and so on are less impacted. The first four indexes in groundwater are less impacted by the surface sewage because of their protogenesis, and heavy metal components become less due to sediment filtration. Data also show that deep groundwater is less influenced, on the contrary, ammonia nitrogen ion is obviously impacted. On the basis of influence degree as well as range of evaluation, some factors that caused the existing influence were discussed and proposes feasible study direction.     

Impact assessment using DEA of coastal hazards on social-economy in Southeast Asia

Southeast Asian countries suffer from severe coastal hazards each year. A large number of these countries are incurring consequential costs that impact their national economies. It is crucial, therefore, to analyze the impact of such hazards on their economic development and provide a solid basis for future development strategies. The purpose of this paper is to assess the relationship between the economic development and the losses from coastal disasters, and to identify both the impact of hazards on the development, as well as the function of such development on the resilience to hazards. The data envelopment analysis (DEA) method is employed to build the assessment models. Data from 1995 to 2005 from eight Southeast countries are analyzed using the DEA models. A set of “resilience index” of these countries are concluded from the results. It is found that the economic development does not contribute to the strengthening of national resilience to coastal hazards. Inappropriate development could even impair the resilience. Additionally, the resilience to coastal hazards is impacted by various factors such as the allocation of resources and external assistance. From the analysis, a clear image is gained of the interaction between economic development and coastal hazards, which provides a basis for future development strategies.

黔东南火烧寨金(锑)矿床地质特征及找矿潜力探讨

通过对黔东南雷公山褶断带火烧寨金锑矿床区域成矿地质背景、矿床地质特征的研究分析,提出了该矿床属幔源—混合型地下热卤水的成因观点,探讨了该地区石英脉(构造蚀变岩)型金矿的找矿潜力。     

Managing overcapacity in small-scale fisheries in Southeast Asia

It is now almost universally accepted that most of the nearshore fisheries in Southeast Asia are overfished. It is also accepted that overcapacity is one of the leading causes of this overfishing. The problem of addressing overcapacity in small-scale fisheries in Southeast Asia is much more complex than that of reducing overcapacity in industrial fleets. In order to manage capacity, managers need to measure and understand how much capacity currently exists in the fishery and what is the desirable level of capacity that best meets the set of management objectives. The only feasible solution to overcapacity may be based on a coordinated and integrated approach involving a mixed strategy of resource management, resource restoration and conservation, livelihoods and economic and community development, and restructured governance arrangements. The reduction of overcapacity implies an increased focus on people-related solutions and on communities.     

基于分类回归树算法的东南太平洋智利竹筴鱼渔场预报

为了提高智利竹筴鱼渔场预报水平和满足渔业捕捞生产的需要,利用2002—2008年的东南太平洋公海海域捕捞的中国大型拖网渔船共计15艘的生产统计资料,以及海洋环境数据(包括海表温度、叶绿素a浓度、表温距平、叶绿素a浓度距平、海表温度梯度强度和海面高度异常等数据),基于CART的算法,构建了智利竹筴鱼渔场决策树预报模型。用含1 114条记录的数据集对模型进行训练,并采用ROC方法对该模型诊断中心渔场的准确性进行了分析。最后将该模型应用于2009年各月份的智利竹筴鱼中心渔场预报,并与实际渔场位置进行了对比,结果显示预报渔场与实际生产位置基本一致,表明利用CART决策树方法建立智利竹筴鱼渔场预报模型是可行的。     

黔东南冰雹集中期和集中度气候特征分析

基于贵州省黔东南地区1961―2008年1―12月16个台站冰雹观测资料,引入了表征冰雹事件时间分配特征新参数——冰雹事件集中度和集中期,对黔东南地区冰雹事件年内非均匀性特征进行分析。结果表明:黔东南地区冰雹事件集中度及集中期的平均和异常空间分布均存在很大区域差异,异常空间分布根据地形可分为4个区;从时间演变上看,各区年内冰雹事件集中度与集中期均表现出显著的年代振荡特征,各区年代际变化特征不一致;黔东南区域年内冰雹事件集中度和集中期表现出反向变化趋势。     

东南印度洋各锋位置和走向的季节变化及其与风场变化的关系

利用剖面浮标的温盐观测资料和上层温度观测资料以及ECCO风应力数据研究了东南印度洋各主要海洋锋的位置、走向和风场的季节变化,并初步分析了亚热带锋(STF)和亚南极锋(SAF)的成锋机制.季节平均的夏季和冬季厄加勒斯锋(AF)分别可以延伸到80°E和82°E,AF在多数情况下可能与SAF和南亚热带锋(SSTF)汇合共同通过Kerguelen-Amsterdam Passage.在克尔盖伦海台以东海盆区,冬季SAF和PF的路径均比夏季偏南,在其他海域二者路径的季节差别不大.克尔盖伦海台以东的深海盆由北向南正负风应力旋度高值中心交替出现,且位置季节变化很小.85°~105°E之间零风应力旋度线位置冬季比夏季偏北.STF位于辐聚区,埃克曼抽吸导致的表层水辐聚可能是STF产生和维持的原因.SAF位置的季节南北摆动幅度小于风应力零旋度线的季节摆动幅度,夏季SAF位置略偏于风应力正旋度区,而冬季大多位于负旋度区,因此风应力旋度不是SAF形成的直接原因.     

甘东南流动台阵微震监测结果

利用高密度宽频带流动台阵资料,应用网格搜索地震定位方法对甘东南2009年11月-2011年11月期间的微震进行了重新定位.在研究区内有3个以上台站记录到的微震共3 014个,比常规台网记录多1 693个.重新定位结果显示:在各断裂带附近地震分布更加密集,沿断裂呈带状或簇集状分布;震源深度分布优势范围为5～20 km,其平均深度为11 km;地震深度分布与断裂的关系密切,地震条带与断裂构造可以较好的相对应.